Juliet came to her decision through love. Juliet loved Romeo, and was willing to do whatever it took to be with him. The potion worked perfectly, but Romeo did not receive Friar Lawrence's message in Mantua, so therefore the plan does not work as intended. Romeo drinks poison ans dies at the foot of Juliet's "grave". When Juliet wakes up, she stabs herself with Romeo's dagger, and dies next to him in the Capults' burial vault.
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